Retailers such as Barnes & Noble will be able to sell access to the online archive of 10 million out-of-print books to users on any Internet-connected device they choose, the Internet company says.

In an effort to quell its critics, Google Inc. on Thursday said it would open up its vast digital books archive to rival retailers who can access the books and sell them online.

The announcement, made during a congressional hearing before the House Judiciary Committee on Google's book-scanning project, involves digital copies of millions of so-called orphan books, works that are still under copyright but whose rights holders can't be tracked down.

Since 2004, the Mountain View, Calif., technology company has scanned more than 10 million books provided by publishers and libraries, and allowed people to search the texts within those books. In 2006, the Authors Guild and the Assn. of American Publishers sued Google, alleging copyright infringement.

Google settled the lawsuits last year by agreeing to split the revenue it would receive from selling access to out-of-print books under copyright protection, with Google retaining 37% and publishers and authors taking 63%. For orphan books, the money would be held in escrow for five years, or until an author or publisher stepped forward to claim the work. The settlement is awaiting court approval before it can go into effect.

But opposition to the settlement has begun to build in recent months. Some critics have questioned Google's commitment to protect the privacy of its readers, while others have voiced concern about a potential Google monopoly of orphaned books.

To appease the first set of concerns, Google last week released more detail on how it would treat reader privacy, saying, for example, that it would not release what books its users have perused unless compelled by court order.

The most recent announcement to make its archive available to all booksellers is aimed at addressing the second set of objections, that the settlement creates a Google monopoly.

"We believe strongly in an open and competitive market for digital books," Google said in a statement. "As part of that commitment, today we announced that for the out-of-print books being made available through the Google Books settlement, we will let any book retailer sell access to those books. Google will host the digital books online, and retailers such as Amazon, Barnes & Noble or your local bookstore will be able to sell access to users on any Internet-connected device they choose."

The announcement did not appease some critics, who said the proposal still leaves Google in near-complete control of the digital files.

"I fail to see what's really new here," said Peter Brantley, a director at the Internet Archive, a San Francisco nonprofit organization that collects and makes available various publicly available content free of charge. "It's like Macy's telling Sears, 'You can sell Macy's clothing.' There's no fundamental change of the conditions under which Macy's acquires those clothes. Google remains in control."